Maxtor VL 17 Control Diagnostic Registers, Alternate Status Register, Device Control Register

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HOST SOFTWARE INTERFACE

Control Diagnostic Registers

These I/O port addresses reference three Control/Diagnostic registers:

I/ O PORT

READ

WRITE

 

 

 

3F6h

Alternate Status

Fixed Disk Control

 

 

 

3F7h

Digital Input

Not used

 

 

 

Alternate Status Register

Contains the same information as the Status register in the Task File. However, this register may be read at any time without clearing a pending interrupt.

Device Control Register

Contains the software Reset and Enable bit to enable interrupt requests to the host. Bit definitions follow:

7

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

0

0

0

0

0

SRST

IEN

0

 

 

 

 

 

 

 

 

 

 

 

 

 

Reset

IRQ Enable

 

 

 

 

 

 

 

 

 

Reset – Setting the software Reset bit holds the drive in the reset state. Clearing the bit re-enables the drive. The software Reset bit must be held active for a minimum of 5 µsec.

IRQ Enable – Setting the Interrupt Request Enable to 0 enables the IRQ 14 signal to the host. When this bit is set

to 1, IRQ14 is tri-stated, and interrupts to the host are disabled. Any pending interrupt occurs when the bit is set to 0. The default state of this bit after power up is 0 (interrupt enabled).

Digital Input Register

Contains information about the state of the drive. Bit definitions follow:

7

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

x

-WG

-HS3

-HS2

-HS1

-HS0

-DS1

DS0

 

 

 

 

 

 

 

 

Reserved

 

Head

Head

Head

Head

Drive

Drive

 

Gate

Select 3

Select 2

Select 1

Select 0

Select 1

Select 0

 

 

 

 

 

 

 

 

Bit 7 of the host data bus is not driven when this register is read.

-Write Gate – Reflects the state of the active low write gate signal on the drive.

-Head Select 3 through -Head Select 0 – Represents the ones complement of the currently selected head number.

-Drive Select 1 – Is 0 if drive 1 selected; 1 otherwise.

-Drive Select 0 – Is 0 if drive 0 selected; 1 otherwise.

6 – 5

Image 47
Contents HA RD Drive Produc T MA Nual DiamondMaxVL REV EC no Section Description Date U T I O N Before You BeginContents Handling and Installation Product SpecificationsHost Software Interface AT Interface DescriptionGlossary Interface CommandsService and Support Figures Abbreviations IntroductionMaxtor Corporation Manual OrganizationNumbering Signal ConventionsConventions Key WordsProduct Description DiamondMax VL 17 Key FeaturesFunctional / Interface Product FeaturesDefect Management Zone DMZ On-the-Fly Hardware Error Correction Code ECCLogical Block Addressing Cache Management Major HDA Components Dual Drive Support Subsystem ConfigurationJumper Location/Configuration Cylinder LimitationModels and Capacities Product SpecificationsDrive Configuration Performance SpecificationsParameter Standard Metric Physical DimensionsEnvironmental Limits Power RequirementsPower Mode Definitions EPA Energy Star ComplianceShock and Vibration Reliability SpecificationsCanadian Emissions Statement Safety Regulatory ComplianceRadiated Electromagnetic Field Emissions EMC Compliance Important Notice Handling and InstallationHard Drive Handling Precautions Pre-formatted DriveMulti-pack Shipping Container Unpacking and InspectionRepacking Physical InstallationRecommended Mounting Configuration Drive Identification Information Handling PrecautionsTools for Installation System RequirementsHard Drive Identification General RequirementsMounting Drive in System Systems Using Cable SelectInstalling 5.25-inch Mounting Brackets and Rails Installing in a Device BayAttaching System Cables Attaching Interface and Power CablesBios Cmos Parameters System SetupSetting the Bios Cmos Hard Drive Preparation System Hangs During Boot Pin Description Summary Interface ConnectorPIN Signal AT Interface DescriptionPin Description Table PIN Name Signal Name Signal DescriptionPIO Timing Timing Parameters ModeDMA Timing Ultra DMA Timing Mode MIN MAXSustained Ultra DMA Data In Burst Device Terminating an Ultra DMA Data In Burst Initiating an Ultra DMA Data Out Burst Device Pausing an Ultra DMA Data Out Burst Device Terminating an Ultra DMA Data Out Burst Task File Registers Error RegisterFeatures Register Host Software InterfaceDevice/Head Register Sector Count RegisterSector Number Register Cylinder Number RegistersCommand Register Summary Command Name Command Code Parameters UsedTimer Value TIME-OUT Period Digital Input Register Control Diagnostic RegistersAlternate Status Register Device Control RegisterInterrupt Handling Reset and Interrupt HandlingReset Handling Set Feature Commands Interface CommandsRead Verify Sectors Read CommandsRead Sectors Read Multiple Read DMAWrite Verify Sectors Write CommandsSet Multiple Mode Write SectorsWrite DMA Write MultipleValue Description Set Feature CommandsSet Features Mode Power Mode Commands Sleep Mode Identify Drive Initialization CommandsWord Content Description 15-8 = PIO data transfer mode = Write Cache enabled Initialize Drive Parameters Format Track Seek, Format and Diagnostic CommandsExecute Drive Diagnostic Error Code DescriptionExecute S.M.A.R.T A.R.T. Command SetSupport Service and SupportService Policy No Quibble ServiceInternet MaxFax ServiceCustomer Service Glossary Access TimeCylinder Zero Gigabyte GB Logical Block Addressing Read Gate Signal THIN-FILM Media